Pattern drawing method by scanning beam and pattern drawing apparatus

Abstract

A pattern drawing method of drawing a desired pattern on a base material by irradiating an electronic beam and scanning the base material with the electronic beam with a predetermined dose amount, comprising: a first step of drawing a first region on the base material by scanning with the electronic beam with a first dose amount; a second step of drawing a second region on the base material by scanning with the electronic beam with a second dose amount; and a inclining step of inclining a boundary between the first region and the second region to form an inclined surface by conducting a first scanning to scan with the electronic beam with the first dose amount and a second scanning to scan with the electronic beam with the second does amount in a mixed arrangement.

Description

BACKGROUND OF THE INVENTION[0001]The present invention relates to an electronic beam pattern drawing method, a production method of a molding die, a production method of moldings (molded product), and an electronic beam pattern drawing apparatus.[0002]Conventionally, as an information recording medium, for example, CDs and DVDs are widely used. Then, many optical elements are used for a precision equipment such as a reading apparatus for reading these recording media. There are many cases where, for optical elements used for these equipments, for example, optical lenses, from a viewpoint of the cost reduction and size reduction, resin optical lenses rather than glass optical lenses are used. Such a resin optical lens is produced by a general injection molding, and also the molding die for the injection molding is formed by a general cutting processing.[0003]In this connection, in the optical lenses, for example, an optical lens used for the reading apparatus having the interchangeab...

AI Technical Summary

Benefits of technology

[0052](3-5) An electronic beam drawing method according to (3-4), wherein it is drawn by adjusting the number of the scanning line which is drawn by the first dose amount and the number of the scanning line which is drawn by the second dose amount, so that the duty ratio of the concave part formation portion to one pitch of the concave convex part formation portion is decreased stepwise as the height of the inclination portion faces toward a side to be decreased.

[0053](3

Problems solved by technology

As a method for drawing processing such a material, there is a limitation in the conventional cutting processing or laser processing.

Further, as an another problem, when the diffractive ring-shaped zonal structure of the binary pattern or blaze shape, is approximated by a polygon and drawn, as compared to a case where the diffractive ring-shaped zonal structure of the binary pattern or blaze shape is formed by an ideal circular pattern drawing, the lowering of optical characteristic of the optical lens, particularly, lowering of the diffraction efficiency are caused, further, because the portion of the joint of the drawing line in the apex of the polygon is conspicuous, when the quality of the products is considered, there is a problem that the products value is lowered from its appearance.

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